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This paper investigates the methods used for gravity pipe inspection. However, a discussion of pipe inspection methods cannot truly happen without and understanding of the preliminary process of pipe prioritization. This is because the vast amount of just gravity pipeline system in use today. For instance, the amount of time, money and resources to aimlessly inspect all suspected pipelines in India alone would be astronomical. So, presented here is a reason why the employment of algorithms and analysis tools must be used to priorities the pipeline systems to see which one need inspection for further analysis. The study goes on to describe innovative techniques used for pipe inspection itself and what kind of innovations should have more attention such as wave and sound analysis that allow for greater inspection rates. This research gives a brief overview of the process of pipe inspection and aspect of cost saving algorithms that can allow more efficiency to enter the field.